The present invention relates to a system for measuring the level of filling, particularly in a fuel tank, having an analog probe which extends over the filling-level range and supplies measurement values which are analogs to the level of filling.
Various arrangements and systems are known for measuring the level of filling, particularly in fuel tanks. Thus, for instance, conductive paths of temperature-dependent resistance are applied to foils and acted on for a short time by a current. From the increase in resistance caused by the heating, the extent to which the conductive path is covered with fuel is then established. The electric value thus derived, which is analog to the filling level, can be fed to an indicating instrument or a digital display.
The foil which bears the conductive paths is arranged, in a suitably shaped holder, vertically in the fuel tank and extends over the entire filling-level region.
Due to various factors such as, in particular, the aging of the foil and the composition of the liquid to be measured, the sensitivity of such a filling-level measuring device varies with time. Furthermore, after it is produced it must be calibrated in order to compensate for manufacturing tolerances.